But the flyover runs the risk of missing the deadline as STU will not be set up by September to prevent damage in the event of an earthquake, said Dhaka Transport Coordination Board (DTCB) officials.

"If an earthquake jolts the city, it may destroy the flyover," a top DTCB official said, asking not to be named.

The DTCB asked the Roads and Highways Department (RHD), the implementing agency, and the consultant to install STU without delay. The RHD ordered STU two months ago to be purchased from the US at about Tk 70 lakh.

"If the RHD had asked for STU at least six months back, the flyover could have met the deadline," the official said.

Builders have completed 78.25 percent of construction of the first ever flyover, including two ramps and railings in a Tk 130 crore project that began on December 6, 2001.

DTCB Executive Director Quamrul Islam Siddiqui said: "We have asked the consultant and the RHD to minimise the delay and keep the traffic flow uninterrupted until STU is installed."

"A total of 400 segments have been complete. With the monsoon passing by, the fixing of other segments will gain speed," he said.

The RHD blamed the failure to meet the deadline on the DTCB. "STU is generally installed after construction is over and more than 20 percent of the work is incomplete which is not RHD's fault," a high official of the project said, declining to be named.

The flyover stretching 1.01km from Shaheen College is expected to reduce traffic snarl-ups on the Airport Road.

The construction work is seriously hampering traffic movement on the important road at rush hour. Although authorities are allowing traffic movement through the cantonment area, gridlock is commonplace in Mohakhali.

It is alleged that maintenance of the diversion roads around the flyover has been neglected, adding to inconvenience of people.